The 1958 United States Senate election in Maine was held on September 8, 1958, to elect a United States senator. Incumbent Republican Senator Frederick G. Payne lost re-election to a second term, losing by a wide margin to Democrat Edmund Muskie, the popular incumbent Governor of Maine.
This was one of a record 15 seats Democrats gained from the Republican Party in the 1958 United States Senate elections. This was the first time Democrats won a Senate race in Maine since the 1910 election for this seat, thus this was the first time a Democrat was popularly elected to the Senate from Maine.
Governor Muskie was unopposed for the Democratic nomination.